Apparatus for and method of fumigating



W. W. HINDS APPARATUS FOR AND METHOD 0E FUMIGATING Filed July 8, 1933 Jan. F 1936..

INVENTOR 24%;, 4/ Mad:

BY Q. "e M- ATTORNEY Patented Jan. 7, 1936 UNITED STATES PATENT OFFICE APPARATUS FOR AND LMETHOD OF FUMIIGATING William W. Hinds, Kansas mesne assignments, to

City, Mo., assignor, by Calcyanide Products 4 Claims.

This invention relates to fumigation, and particularly to a compact, efiicient and economical apparatus for distributing lethal gases.

While the invention is applicable to facilitate the use of gaseous insecticides, larvicides and fungicides derived from solid materials, it is particularly useful in the application of hydrocyanic acid gas which is released by contact of air with calcium cyanide. Calcium cyanide is an unstable compound which, when exposed to air containing moisture in the amount normally present In the atmosphere, decomposes and releases bydrocyanic acid gas. This lethal gas is employed widely in the extermination of various pests and vermin.

It is the object of the present invention to provide an apparatus of simple construction which may be conveniently packed for transportation and readily assembled for use.

A further object of the invention is the provision of an apparatus in which a large volume of air may be brought into contact with a solid material from which the lethal gas is derived, so that the gas may be formed conveniently and conveyed to the space to be fumigated.

Other objects and advantages of the invention will be apparent as it is better understood by reference to the following specification and accompanying drawing, in which the figure is a sectional view of the apparatus and of a chamber in which the lethal gas is utilized.

In carrying out the invention, the shape and form of the apparatus used may be varied. In principle, it embodies a collapsible filter through which air may pass while the solid materials are retained, a surrounding chamber of gas-impervious material also preferably collapsible, an outlet to which a conduit may be connected, and means for supplying air to the apparatus, including preferably means for feeding solid material which is adapted to release a lethal gas when exposed to air.

In the preferred form of apparatus, I employ a cone-shaped chamber 5 with a surrounding chamber 6, the latter forming a part of the outlet and being supported on legs I which for convenience may be detachable. At the bottom of the chamber 5 a cone-shaped extension 8 is secured by clamps 9 which engage flanges III and II.

The chamber 5 is preferably corrugated as indicated at I2 near its upper edge, and a bag l3 of cloth or other suitable material, impervious to fine dust but capable of permitting air to pass therethrough, is connected in any suitable manner, as for example by a wire band M. The chamber 6 is likewise preferably corrugated at I5 and a bag I6 is secured thereto in any suitable manner, as for example by a wire band H. The bag I6 is rubberized or otherwise rendered 5 impervious to gases, so that air and lethal gases generated in the apparatus and permitted to pass through the bag I3 are directed downwardly into the chamber 6.

One or more outlet nipples I8 may be provided 10 in the wall of the chamber 6, and conduits I9 may be connected thereto, for example by means of a bayonet joint 20. Conduit I9 may extend into any convenient space to be fumigated, indicated at 23, so that vermin existing within the 15 space will be subjected to the lethal eifect of the gas. It will. be understood that if only one outlet is employed, the remaining outlets from the chamber 6 may be closed by a suitable cap I9.

To supply air to the apparatus, I may provide 20 a blower 2| of any convenient form which may be actuated by an electric motor or other source of power. A simple blower such as those employed in vacuum cleaners is efiicient and suitable for the purpose. The air may be drawn into the blower through any suitable inlet. It is, however, usually convenient to connect a conduit 22 to the inlet, the end of the conduit being disposed within a receptacle 22 containing a supply of the solid material which, when exposed to air, releases a lethal gas.

In the use of the apparatus as described, a suitable agent such as calcium cyanide may be placed in the receptacle 22'. Usually from three to five pounds of powdered calcium cyanide is employed, but the amount used will depend upon the amount of fumigation which may be needed, and of course the apparatus may be constructed in various sizes so that the charge will vary accordingly. Air drawn from the atmosphere surrounding the apparatus is introduced by means or the blower to the apparatus. The solid material is drawn in with the air. Contact of the air with the calcium cyanide releases hydrocyanic acid gas, which passes through the bag I3 and is directed through the conduit I9 into the chamber. All of the solid material is retained within the bag I3 and chamber 5, and the space to be fumigated is subjected only to the action of the gaseous fumigating agent which is carried by the air introduced by the blower.

The apparatus may be used conveniently for fumigating a number of rooms in a building simultaneously, particularly where a hot air heating system is provided. In that case, it is merely necessary to introduce the discharge conduit l9 into the distributing system for hot air. By the operation of the apparatus, the gaseous fumigating agent will be distributed into all spaces having outlets from the heating system.

The apparatus is also particularly useful in fumigating machines, grain elevators or passages where it is not desirable to introduce solid material such as calcium cyanide. By utilizing the apparatus, only the gaseous fumigating agent enters the space to be fumigated, and there is no deposit of dust or solid residue when the fumigating is completed.

The apparatus is particularly convenient because the bags l3 and I6 are collapsible, the outlet and inlet conduits may be separated from the apparatus, the legs may be removed, and all of the parts may be packed in a small case. Transportation of the apparatus is thus facilitated. It can be assembled conveniently and quickly at the place where it is to be employed, and as indicated the apparatus may be utilized in various ways in applying the lethal gas to the space to be fumigated.

Various changes may be made in the details of construction and arrangement of the parts without departing from the invention or sacrificing any of the advantages thereof.

I claim:

1. In a fumigating apparatus, inner and outer containers, the inner container being at least in part pervious to gases but impervious to finely divided solids, and the outer container being impervious to gases, a blower for blowing a gas into the inner container, means for directly connecting the intake side of the blower with a source of a fumigant, and means for conducting gas from the space between the inner and outer containers.

2. In a fumigating apparatus, inner and outer containers, the inner container being at least in part pervious to gases but impervious to finely divided solids, and the outer container being impervious to gases, the bottom of the inner container converging downwardly, a blower for blowing a gas into the inner container adjacent the bottom thereof, means for directly connecting the intake side of the blower with a source of fumigant, and means for conducting gas from the space between the inner and outer containers.

3. In a fumigating apparatus, a base member comprising a downwardly converging generally conical chamber, and a wall surrounding at least a part of said conical chamber and forming a surrounding chamber, inner and outer containers attached respectively to the walls defining said chambers, the spaces enclosed by the inner and outer containers being in communication with the conical and surrounding chambers, the inner container being pervious to gases but impervious to finely divided solids, and the outer container being impervious to gases, means for blowing gas into the conical chamber adjacent its lower end, and means for conducting gas from the surrounding chamber.

4. The method of fumigating in which a solid substance capable of releasing a fumigating gas when brought in contact with air is utilized as the source of fumigant, which comprises entraining such a solid substance in a blast of air, conducting the blast of air and entrained solid substance into an enclosure, separating solid particles in said enclosure and conducting the gas freed of solid particles to the place of use.

WILLIAM W. HINDS. 

